The Fallopian tubes are the site for fertilization before the embryo makes its way to the uterine cavity for implantation. If the Fallopian tubes are damaged, fertilization may not occur. If one Fallopian tube is blocked, it may be due to inherent disease involving both Fallopian tubes; even if the other Fallopian tube is open, it may not be able to provide the appropriate nurturing environment for fertilization and early embryo growth to take place.

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.
Cancer. Although some early studies suggested there may be a link between certain medications used to stimulate egg growth and the development of a specific type of ovarian tumor, more-recent studies do not support these findings. There does not appear to be a significantly increased risk of breast, endometrial, cervical or ovarian cancer after IVF.

Initial blood work, cycle tracking and fertility analysis is done. To begin IVF, your doctor or fertility specialist will evaluate your hormone levels and menstrual cycle to determine what medications and plan of action may be needed. You may also undergo a transvaginal ultrasound to examine your ovaries and reproductive system, ensuring that they are healthy.
The main cause of male infertility is low semen quality. In men who have the necessary reproductive organs to procreate, infertility can be caused by low sperm count due to endocrine problems, drugs, radiation, or infection. There may be testicular malformations, hormone imbalance, or blockage of the man's duct system. Although many of these can be treated through surgery or hormonal substitutions, some may be indefinite.[57] Infertility associated with viable, but immotile sperm may be caused by primary ciliary dyskinesia. The sperm must provide the zygote with DNA, centrioles, and activation factor for the embryo to develop. A defect in any of these sperm structures may result in infertility that will not be detected by semen analysis.[58] Antisperm antibodies cause immune infertility.[23][24] Cystic fibrosis can lead to infertility in men.
Patients with hypothalamic dysfunction are not producing signals within their brains to tell the ovary to mature an egg. They are diagnosed because they have an extremely low FSH and a low LH (almost zero). Neither clomid nor letrozole will help them. For these patients, IUI must be accompanied by gonadotropin to be effective. From here on in this section, none of the data we’ll reference refers to patients with hypothalamic dysfunction.
Some research has found that IVF may raise the risk of some very rare birth defects, but the risk is still relatively low. Research has also found that the use of ICSI with IVF, in certain cases of male infertility, may increase the risk of infertility and some sexual birth defects for male children. This risk, however, is very low (less than 1%).

Risk of ovarian hyperstimulation syndrome (OHSS). OHSS can happen when women respond too well to fertility drugs and produce too many eggs. About 10 to 20 percent of women who take gonadotropins develop a mild form of OHSS, a condition marked by weight gain and a full, bloated feeling. Some also have shortness of breath, dizziness, pelvic pain, nausea, and vomiting. If you have OHSS, your ovaries swell to several times the normal size and produce fluid that accumulates in your abdominal cavity. Normally this resolves itself with careful monitoring by a physician and bed rest. But in rare cases it's life threatening, and you may have to be hospitalized for more intensive monitoring or treatment.

We know this is a touchy subject, but unfortunately, there’s no way around it. Science says that age does play a role in fertility. This 2018 study correlated age as a statistically significant factor in secondary infertility compared to primary infertility. In the study, the average age of couples was higher among those experiencing secondary infertility.
Preimplantation genetic screening (PGS) or preimplantation genetic diagnosis (PGD) has been suggested to be able to be used in IVF to select an embryo that appears to have the greatest chances for successful pregnancy. However, a systematic review and meta-analysis of existing randomised controlled trials came to the result that there is no evidence of a beneficial effect of PGS with cleavage-stage biopsy as measured by live birth rate.[81] On the contrary, for women of advanced maternal age, PGS with cleavage-stage biopsy significantly lowers the live birth rate.[81] Technical drawbacks, such as the invasiveness of the biopsy, and non-representative samples because of mosaicism are the major underlying factors for inefficacy of PGS.[81]

IVF success rates are the percentage of all IVF procedures that result in a favourable outcome. Depending on the type of calculation used, this outcome may represent the number of confirmed pregnancies, called the pregnancy rate, or the number of live births, called the live birth rate. The success rate depends on variable factors such as maternal age, cause of infertility, embryo status, reproductive history, and lifestyle factors.
New Brunswick provides partial funding through their Infertility Special Assistance Fund – a one time grant of up to $5,000. Patients may only claim up to 50% of treatment costs or $5,000 (whichever is less) occurred after April 2014. Eligible patients must be a full-time New Brunswick resident with a valid Medicare card and have an official medical infertility diagnosis by a physician.[150]
In humans, infertility is the inability to become pregnant after one year of intercourse without contraception involving a male and female partner.[2] There are many causes of infertility, including some that medical intervention can treat.[3] Estimates from 1997 suggest that worldwide about five percent of all heterosexual couples have an unresolved problem with infertility. Many more couples, however, experience involuntary childlessness for at least one year: estimates range from 12% to 28%.[4] Male infertility is responsible for 20–30% of infertility cases, while 20–35% are due to female infertility, and 25–40% are due to combined problems in both parts.[2][5] In 10–20% of cases, no cause is found.[5] The most common cause of female infertility is ovulatory problems, which generally manifest themselves by sparse or absent menstrual periods.[6] Male infertility is most commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity.[7]