Embryos are transferred to the uterus. Embryos that have developed from the fertilization process will be placed in the uterus, normally 3 to 5 days after retrieval, so that they can embed. If this process is successful, pregnancy will occur and IVF is considered a success. If it’s not, you may use a frozen embryo that you have saved from a previous round of IVF to try again.
Since each couple is unique in the cause of infertility, the answer as to whether ICSI or conventional IVF is more beneficial could vary. A retrospective cohort study published in 2015 is the most comprehensive study so far comparing the two strategies with different infertility factors, which will be the focus here1. A few other smaller-scale studies will also be discussed.
Ovarian stimulation – You’ll take stimulation medications to increases both the quantity and quality of eggs. This usually begins during days 2-4 of your cycle and continues for around ten days. You’ll be closely monitored during this time to track your uterine lining, follicular development, and hormone levels. Once the follicles are optimal size, a trigger medication is given to fully mature the eggs.
The laboratory – This is when the harvested eggs are fertilized by an embryologist. Once fertilized, they’re grown 3-5 days until they’re able to be transferred into the woman’s uterus. Prior to the transfer, the embryos can be genetically tested. Although testing isn’t right for everyone, it’s useful for some people as it may help prevent miscarriage, passing on known genetic disorders, and can also be used to choose the sex of the child.
In 2006, Canadian clinics reported an average pregnancy rate of 35%. A French study estimated that 66% of patients starting IVF treatment finally succeed in having a child (40% during the IVF treatment at the centre and 26% after IVF discontinuation). Achievement of having a child after IVF discontinuation was mainly due to adoption (46%) or spontaneous pregnancy (42%).
If you're overweight or obese, losing weight can boost your chances of getting pregnant. A study found that women whose body mass index (BMI) was above normal took twice as long to get pregnant as those with a normal BMI. But a drop in weight of 5%-10% can dramatically improve ovulation and pregnancy rates. Obesity can also cause infertility and low testosterone in men. Being significantly underweight can also lead to infertility.
Prior to the retrieval procedure, you will be given injections of a medication that ripens the developing eggs and starts the process of ovulation. Timing is important; the eggs must be retrieved just before they emerge from the follicles in the ovaries. If the eggs are taken out too early or too late, they won't develop normally. Your doctor may do blood tests or an ultrasound to be sure the eggs are at the right stage of development before retrieving them. The IVF facility will provide you with special instructions to follow the night before and the day of the procedure. Most women are given pain medication and the choice of being mildly sedated or going under full anesthesia.
Problems with your periods or menstrual cycle is a sign of ovulation problems – and if you aren’t ovulating, you won’t get pregnant. Menstrual problems are the most obvious sign of infertility in women – but they don’t necessarily mean you’re infertile. Most women have some type of problem with their period: light flow, heavy flow, clotting, irregularity caused by stress or weight fluctuations, hormonal changes, etc.
A genetic disorder. If you or your partner is at risk of passing on a genetic disorder to your child, you may be candidates for preimplantation genetic testing — a procedure that involves IVF. After the eggs are harvested and fertilized, they're screened for certain genetic problems, although not all genetic problems can be found. Embryos that don't contain identified problems can be transferred to the uterus.