Do IVF Babies Look Like Both Moms? Genetics, ROPA, and UK Options in 2025

• 19 Sep, 2025
• Rohan Talvani
• 0 Comments

TL;DR

• Most IVF babies inherit physical traits from the egg provider and the sperm provider. The carrying mum does not add nuclear DNA.
• In ROPA or reciprocal IVF, one mum gives eggs and the other carries. Only the egg mum is a genetic parent, but the carrying mum can still influence health and sometimes subtle features through epigenetic effects.
• Mitochondrial donation can add a tiny set of genes from a second mum, but these genes do not code for eye colour, face shape, or height. It is tightly regulated in the UK and used for specific medical cases.
• You can tilt resemblance toward the non-genetic mum by choosing a donor with similar features, using family photos, and keeping donors consistent across siblings.
• UK specifics: HFEA consent forms establish legal parenthood; funding and access vary by local NHS policy. Private costs and waiting times differ by clinic.

What makes an IVF baby resemble one or both mums

The short answer first. A baby looks like the people who pass on nuclear DNA. In a two-mum IVF journey, that is the egg provider and the sperm provider. The mum who carries the pregnancy shapes the baby in powerful ways, but she does not usually pass nuclear DNA that sets eye colour, face shape, or freckles.

That is why two women can feel equally like mum, yet only one shares that genetic link unless you use a niche medical route like mitochondrial donation. Even then, the visible traits most of us think about when we say looks do not come from mitochondria.

Here is the basics, no jargon. Physical resemblance mostly comes from nuclear DNA, the genetic code inside the cell nucleus. In IVF, the egg carries half the nuclear DNA and the sperm carries the other half. The uterus that grows the baby is not adding more nuclear DNA. So the baby tends to resemble the egg mum and the sperm donor or partner.

Now the bit that often gets missed. Pregnancy is not a passive container. The carrying mum sets the environment the embryo grows in. That environment can switch genes on or off like dimmer switches. Scientists call this epigenetics. UK and US fertility bodies, including HFEA and ASRM, acknowledge that the uterine environment can change methylation patterns that influence growth, metabolism, and sometimes how certain traits show up. Think birth size, stress response, long term metabolic risk. Not eye colour or bone structure, but still meaningful. There is research in Nature and other journals over the last decade that shows placental and fetal gene expression responding to signals from the endometrium.

So what might you notice in real life? Families often report that babies born through reciprocal IVF pick up dad like features from the donor and bone structure or eye shape from the egg mum. Then, down the line, people start saying the baby has the carrying mum’s expressions, smile, or the way they hold themselves. Some of that is learned and social, some may be tiny epigenetic nudges. Either way, you can feel represented without both mums supplying nuclear DNA.

What about rare routes that mix DNA from two mums? In the UK, mitochondrial donation can place nuclear DNA from one mother into a donor egg with healthy mitochondria. That means a fraction of the baby’s genes come from a second woman, but those mitochondrial genes run the cell’s powerhouses. They do not code for facial shape or hair colour. The UK first approved this in 2015 and announced early births in 2023 through the Newcastle programme. It is only allowed to avoid severe mitochondrial disease, after strict approval, and not for resemblance.

One more frontier you might have seen in headlines. Lab-made eggs or sperm from skin cells, called in vitro gametogenesis, has worked in mice and is under basic research in humans. It is not available in clinics. It is not a path to combine nuclear DNA from two women in UK practice in 2025.

Bottom line for looks. Expect the baby to resemble the egg mum and the sperm provider, and to pick up the carrying mum’s influence on health and sometimes subtle features through pregnancy and upbringing. If you want the baby to lean toward the non-genetic mum’s vibe, you can choose a donor who matches her features, and keep donor choice consistent across siblings.

Paths for two mums in the UK and what each means for resemblance

If you clicked on this, you likely want practical options. Here is how two-mum families usually build a genetic and emotional connection, and what to expect from each route when it comes to resemblance.

Route 1. Reciprocal IVF ROPA. One mum provides eggs, the other carries the pregnancy. This is sometimes called partner assisted reproduction. The baby’s nuclear DNA comes from the egg mum and the sperm donor or known donor. The carrying mum gives the baby a home to grow, and that can affect birth weight, immune development, and long term health markers. In day-to-day life, many families feel both mums are reflected: one in inherited features, the other in expressions and physiology shaped during pregnancy.

Route 2. IVF where the same mum provides eggs and carries. If one partner both supplies eggs and carries, she is the genetic and gestational mother. The other mum can still be the legal second parent in the UK through HFEA consent at a licensed clinic. Resemblance will usually track the genetic mum and the sperm provider. Some couples pick a donor who looks like the non-carrying mum to spread the likeness.

Route 3. Reciprocal IVF with alternating roles across siblings. If both mums want a genetic link across the family, you can split roles over time. For baby one, Mum A provides eggs and Mum B carries. For baby two, switch. Use the same donor if you want the siblings to share the donor side, which helps bring the children into the same resemblance cluster. Planning this early lets you freeze embryos or eggs while age is on your side.

Route 4. IVF with donor eggs and one mum carries. This is common if neither partner can or wants to undergo egg collection. The baby will resemble the egg donor and sperm donor or partner. You can still align features with the carrying mum by choosing a donor whose traits match hers. In the UK, HFEA registries allow clinics to profile donor traits like hair, eye colour, height, ethnicity, and sometimes hobbies or subjects studied.

Route 5. Mitochondrial donation. As noted, this can put a second woman’s mitochondrial DNA into the mix alongside the nuclear DNA from an intended mother. The aim is to avoid serious disease, not to adjust looks. Approved case by case by the HFEA and specialised centres. Not a path to shared eyes or cheekbones.

What does real resemblance look like over time? Newborns tend to resemble everyone and no one. Chubby cheeks and newborn puffiness hide features. By six to twelve months, face shape, eye colour, and hair patterns settle a bit. By five to seven years, bone structure and teeth make resemblance more obvious. Heritability estimates for height are high, often 70 to 80 percent in twin studies; for facial specifics, we know there is strong genetic control, but many genes with small effects. That is why you can see a photo and say, that is her mother’s jawline, even if the child learned mum’s smile from shared moments.

Choosing a donor to reflect the non-genetic mum. This is where you have real influence. Many UK clinics will match donors using family photos and descriptions you provide. You can ask for donors who share eye colour, hair texture, complexion, and even facial vibe, though the last bit is subjective. If that feels important to you both, say it early. Things that help clinics match well include a few natural light photos, a short note about family traits like prominent cheekbones or curly hair in childhood, and any known health patterns you want to avoid or include. HFEA rules ensure donors provide family health history, which matters more than looks long term.

Heuristics to keep in mind when you care about resemblance. If one mum wants that strong genetic link, have her be the egg provider in the first pregnancy. If both want it, alternate and freeze embryos early. If the non genetic mum wants to feel represented in looks, choose a donor who matches her features and family vibe. Keep the same donor for future siblings if you want a coherent family resemblance. If carrying is important to both, take turns carrying, even if the same partner provides eggs twice.

Where the science stands in 2025. HFEA is the gold standard for clinic oversight and donor rules in the UK. ASRM and ESHRE publish guidance on epigenetics and perinatal outcomes in assisted reproduction. The consensus is steady. The carrying mum shapes epigenetic patterns that touch growth and metabolic health, and those patterns do not rewrite nuclear DNA based traits like eye colour. That is why you get a baby who is genetically one mum and the donor, but still feels like both mums in the room.

Steps, examples, checklists, and answers to what people ask next

Here is a practical path you can follow, minus the fluff and drama.

1. Decide what matters most. Genetic link, carrying, or timing. Write it down. If genetics is top for both, plan to alternate egg provider across children.
2. Book a consult at an HFEA licensed clinic. Bring a short brief on goals. Ask about reciprocal IVF, donor options, waiting times, and consent to legal parenthood for same sex couples.
3. Do the screening. AMH, antral follicle count, STI panel, rubella immunity, and any extra tests the clinic suggests based on your history.
4. Pick a donor strategy. Known or clinic donor. If resemblance to the non genetic mum matters, ask for matching based on her features and family photos.
5. Plan the cycle. For ROPA, the egg mum does stimulation and retrieval; the other mum preps her uterus for transfer. Decide fresh versus frozen transfer.
6. Think ahead for siblings. If cost allows, freeze extra embryos. If you want the same donor across children, tell the clinic now and buy extra donor vials while available.
7. Consent and law. Sign the HFEA parenthood forms so both mums are legal parents at birth. Ask the clinic to walk you through it line by line.
8. Budget. In England, NHS funding varies by Integrated Care Board. Some ICBs ask same sex couples to self fund a number of IUI cycles before IVF funding; others have different thresholds. Private IVF often lands in the 5,000 to 8,000 pounds range per cycle before meds and donor costs. Donor sperm can add 800 to 1,200 pounds per vial, meds 1,000 to 2,000 pounds, and add ons vary. Get a written quote.

Example setups with real world trade offs.

• Couple A wants both mums to be represented in the first child. They choose ROPA. Mum A provides eggs at 32. Mum B carries. They pick a donor with Mum B’s hair and eye colour. The baby grows with Mum B and inherits bone structure from Mum A. When a second child comes, they switch.
• Couple B wants to move fast and reduce meds. Mum B has a low AMH and wants to avoid stimulation. They choose donor eggs matched to Mum A’s features and have Mum B carry. The baby will not share nuclear DNA with either mum, but Mum B’s pregnancy and their donor choice pull the child into the family likeness.
• Couple C has a family history of mitochondrial disease. They are referred to a specialist centre to discuss mitochondrial donation. This is rare and medical. They proceed only after HFEA approval and detailed counselling.

Resemblance planning checklist.

• Agree what resemblance means to you. Face shape, colouring, height, or just feeling seen.
• Choose route. ROPA if you want both roles in one pregnancy. Alternate across siblings if you want both mums to be genetic parents over time.
• Donor matching. Share non genetic mum’s photos and family traits. Ask clinics about extended donor profiles where lawful.
• Keep donors consistent across children if you want the siblings to look like they belong to the same set.
• Freeze early if age is a factor. Eggs and embryos made earlier carry lower genetic risk and give you options later.
• Ask about single embryo transfer to reduce twins if that matters for health. The more controlled the pregnancy, the more predictable the perinatal outcomes.

Pitfalls to avoid.

• Assuming carrying means genetic contribution. It does not, unless you are in the niche mitochondrial route, which is not for looks.
• Waiting too long to plan for siblings. Donor availability changes. Buy additional vials early if you want the same donor next time.
• Over indexing on one photo. Babies change a lot in the first two years. Do not judge resemblance too early.
• Skipping legal consent. In the UK, fill the HFEA parenthood forms at a licensed clinic so both mums are legal parents from birth.

Pro tips.

• Ask your clinic how they support ROPA. Not all clinics coordinate both partners’ cycles smoothly. A clinic that does this often will save you stress.
• Collect a few pictures of both mums as babies and teens. It helps donor matching and is a sweet record for your child later.
• If you want a child who resembles the non genetic mum, match donors to her extended family, not just her. Aunties, grandparents, cousins give a fuller picture of traits.
• Think about long term health more than surface looks. Family history, blood disorders, and recessive carrier matches matter. HFEA requires clinics to check donor carrier status; ask how they match you.

Mini FAQ.

Can the carrying mum pass DNA to the baby. Not the nuclear DNA that codes for appearance. There is tiny cell exchange during pregnancy, called microchimerism, but it does not change the child’s traits.

Can epigenetics change looks. Epigenetics can change how genes express, which can affect growth patterns and sometimes body composition. It does not rewrite the code for eye colour or face shape.

Can we choose a donor to look like the non genetic mum. Yes. Many UK clinics will help you match a donor to her features using profiles and photos. Be honest about which traits matter and which you do not mind changing.

Will breastfeeding change how the baby looks. No. It can affect growth rate and health, but it will not change bone structure or eye colour.

What if the baby looks like neither of us. It happens. Genetics is a shuffle. Babies can pick traits from the donor’s grandparents or distant relatives. Over time, shared habits and expressions make children feel like you, even when the jawline came from someone else.

Is mitochondrial donation a way for both mums to share genes. Technically it adds a small set of mitochondrial genes from another woman, but it is not meant for shared parenthood and does not change visible traits. UK use is restricted to very specific medical cases.

How do we make both mums feel included if only one is the genetic parent. Share roles in the cycle. Let the non genetic mum attend scans, give the first cuddle, cut the cord if that is available, and be present in the birth plan. Later, tell the story from day one so your child grows up knowing both mums made them possible in different ways.

UK legal and cost notes you will want to know in 2025.

• Legal parenthood. The woman who gives birth is the legal mother. Her partner can be the second legal parent if you both complete the HFEA consent forms at a licensed clinic before treatment using donor sperm. You can ask your clinic to check the paperwork twice.
• NHS funding. Criteria differ by Integrated Care Board. Some areas require evidence of self funded donor insemination attempts before IVF funding is offered to same sex couples. Your GP can tell you the current policy where you live.
• Private costs. A typical IVF cycle fee is often quoted around 5,000 to 8,000 pounds before medication and donor sperm. Medicines can add 1,000 to 2,000 pounds. Donor sperm is commonly 800 to 1,200 pounds per vial, and you may need more than one. ROPA can include extra coordination fees. Always request a written cost breakdown.

Next steps if you are deciding right now.

• If the goal is for both mums to be represented in one pregnancy, choose ROPA and match the donor to the non genetic mum. Book a clinic that routinely does partner assisted cycles.
• If the goal is for both mums to be genetic parents across time, plan two pregnancies with alternating egg providers and the same donor where possible.
• If you face a mitochondrial disorder, ask your GP for referral to a centre recognised for mitochondrial donation. This is specialised and regulated.
• If you want a quick path with fewer meds, consider who is most ready to carry now and choose donor eggs or embryos that align with your family’s traits and health goals.

Final thought to take home. Looks are part genetics, part the little things you do together every day. In two mum families, kids often grow into a face that feels like home for both of you. That is as real as cheekbones.

Sources and credibility you can trust. HFEA guidance on donor conception and legal parenthood in the UK; ASRM committee opinions on epigenetics and perinatal outcomes in assisted reproduction; peer reviewed studies in journals such as Nature and Human Reproduction on uterine influence on placental and fetal gene expression; UK reports from Newcastle on mitochondrial donation since regulatory approval in 2015 and early births reported in 2023. Your clinic should be happy to show you the latest summaries from these sources in plain language.