Getting pregnant: fertility treatment for US surrogacy

US fertility clinics offer exceptional standards of clinical care for surrogacy. Unlike in the UK, preimplantation genetic testing of embryos is carried out routinely, and other aspects of the process are also carefully controlled, to help maximise the chances of a successful pregnancy. Much more information is also available to intended parents, including enabling them to know (or even to choose, if they wish) the biological sex of the embryo they are transferring.  

US clinicians usually meet with the intended parents at the beginning of their journey to discuss their personal circumstances and create a treatment plan according to whether the intended parents: 

• do not yet have embryos, or
• already have embryos in storage. 

When intended parents don’t yet have embryos and need to create them

Parents who need to create embryos can take some preparatory steps in the UK (or wherever they are living) to improve their chances of success. Same-sex and single dads can do basic fertility screening to check sperm quality if they have not previously had any fertility treatment; those who have already been through fertility treatment may want to gather the most up to date information. Checks can be arranged through most private UK fertility clinics (or outside the UK if the parents live elsewhere) and the results sent to the US clinic and discussed at an initial consultation. 

For parents needing an egg donor it is usually most straightforward to travel to the US to bank sperm as a first step, although some intended parents export sperm from the UK (or elsewhere). An egg donor can start the medication to stimulate her ovaries into producing eggs once she has completed screening and been given medical and legal clearance. She will be closely monitored by scans to see how the follicles in her ovaries are developing and to gauge how many eggs are likely to be collected. When the follicles are developed the donor will be scheduled for the egg retrieval procedure which is performed under anaesthetic.  

Intended parents creating embryos with their own eggs will typically follow a similar process. It is usually possible to start medication at home, and then travel to the US  before the scheduled egg collection date.  

Once the eggs have been retrieved, they will then be fertilised with the intended parents’ sperm (or donor sperm) and the embryos will be monitored while they develop over the next 5-6 days. An embryologist will check the status of the embryos, which will then either be immediately transferred to a surrogate or, more typically, frozen for use at a later date. 

When intended parents want to import stored embryos

It is possible to import embryos into the US from elsewhere, assuming the US clinic will accept the embryos (having reviewed information about how they were created, frozen and stored, and any testing carried out).  Specialist couriers with experience of exporting such precious material can be engaged to transport the embryos safely. 

Waivers from the Food and Drug Administration (FDA) may need to be applied for, and the intended parents may be asked to complete testing to satisfy FDA requirements retrospectively, which normally means a physical exam, and blood and urine tests. If the embryos or gametes are being exported from the UK, the sending fertility clinic in the UK will also need to ensure compliance with the UK’s Human Fertilisation and Embryology Authority (HFEA) regulation which requires checks carried out to ensure the receiving clinic applies appropriate standards. 

What will the surrogate undergo to become pregnant?

The surrogate will be given medication to prepare her uterus for embryo transfer. The timing will depend on the surrogate’s menstrual cycle and the protocol recommended by the clinic, which might be a fully medicated cycle, or a natural cycle supported with a low dose medication. The surrogate will usually need a couple of scans prior to embryo transfer to check that her womb lining has reached the optimal thickness.  

Intended parents often attend the embryo transfer, either virtually or in person, as it is an important milestone in the journey which the surrogate will be keen to share with them. 

Most clinics recommend a home pregnancy test which is usually followed up with a blood test at the clinic. If the result is negative, there will be a discussion around next steps and timing for any next attempt. 

PGT testing and sex selection in US surrogacy

Preimplantation Genetic Testing/Diagnosis (PGT/D) of embryos involves removing a small number of cells from the part of the developing embryo which will ultimately become the placenta, and analysing their genetic makeup in order to inform decisions about which embryos to transfer.  PGT/D is carried out routinely in the US fertility treatment, and contributes to the high success rates since identifying which embryos are chromosomally ‘normal’ can significantly reduce the risk of implantation failure and miscarriage.  Since PGT/D provides information not only about the chromosomal profile of the embryo but also the biological sex of the baby, many intended parents choose the biological sex of the embryos to transfer.  

What affects the chances of a successful pregnancy?

US clinics must publish their success rates and working with a clinic and/or clinician with high success rates is a key component for a positive pregnancy result.   

Egg quality and the age of the egg provider is a significant factor since the rate of chromosomal abnormalities increases with age (most significantly above 35 years old).   

Sperm quality is the other side of the coin, with scope for intended fathers to manage lifestyle choices (including diet and vitamins) to maximise their sperm quality before sperm collection. 

How well the surrogate’s womb responds to the protocol recommended is the third major factor, since if her womb lining reaches the optimal thickness before embryo transfer, there will be a much better chance of a successful pregnancy.