Fertility 411

How In Vitro Fertilization (IVF) Really Works

Here's how it works.
IVF
In vitro fertilisation, computer artwork.Getty Images

Getting pregnant can be one of the most exciting chapters in life — that is, if you want children in the first place. Even if you do, conceiving can be difficult. For some would-be parents, that's where assisted reproductive technology, or fertility treatments that involve both eggs and embryos, comes in. In vitro fertilization (IVF), for example, is an increasingly popular technique for having babies: A 2014 report from the Society for Assisted Reproductive Technology found that IVF led to the births of 1.5 percent of all babies born in the U.S. in 2012, an all-time high.

To get the lowdown on how it works, who can benefit from it, and more, Allure spoke with fertility doctors Brooke Hodes-Wertz, a reproductive specialist and assistant professor of obstetrics and gynecology at NYU Langone Health medical center, and Joel Batzofin, founder of New York Fertility Services. Ahead, what you should know about this increasingly common treatment.

How does IVF work?

When a patient decides to get IVF, they begin by taking medication that helps stimulate the production of eggs. They're monitored by a doctor with blood tests and ultrasounds to make sure they're healthy during the process and that their eggs are maturing; eventually, the practitioner extracts the eggs through the vagina with a needle. Then eggs and sperm are transferred to the same dish, where insemination hopefully occurs; if the semen sample in question has a low sperm count or the sperm are otherwise having a hard time doing their job, an embryologist can also directly inject an egg with a sperm cell. Batzofin says that at this point, depending on what the patients want, they may do something called PGS, or preimplantation genetic screening: "During this procedure, they do testing for healthy embryos to make sure they don't have chromosomal abnormalities or genetic defects." Then the embryo is transferred into a uterus — that of the person who provided the egg or someone else's. Hodes-Wertz tells Allure, "Not all eggs will be mature, fertilize, grow in culture, or lead to a baby, so by increasing the amount of eggs retrieved, you can increase the chances that one of them will lead to a normal healthy baby after all of those steps."

Who typically benefits from IVF?

Hodes-Wertz tells Allure that any couple (or person) who has been unable to conceive after having unprotected vaginal intercourse for more than six to 12 months may benefit from seeking medical advice. (It's at that 12-month mark of trying that a couple generally qualifies as infertile.) She mentions a number of different factors that indicate IVF may be helpful, including low sperm count, fallopian tube issues, diminished ovarian reserve, and recurrent pregnancy loss due to chromosomal abnormalities.

Batzofin says in the 1970s, IVF was initially understood as an option for women with fallopian tubal disease. As the medical community began to better understand the situations in which it could be helpful, its use increased: "Indications grew to include treatment for men who have low sperm count, as well as people with endometriosis, infertility from autoimmune disease, as well as polycystic ovarian syndrome," Batzofin says. He also explains it can be used when a couple wants to avoid passing on a sex-linked disease to their child. If they have a genetic disease in the family that only affects males, for example, they can choose to implant only female embryos. All this said, IVF generally isn't the very first thing doctors recommend for people who don't get pregnant right away. Fertility meds on their own and both intracervical and intrauterine insemination of sperm can also be helpful, depending on the person or couple.

How successful is IVF?

Both doctors agree that the success rates are highly dependent on the age of the patient giving the egg. While Batzofin says sperm quality and uterine quality also matter, egg quality — which generally begins to decline significantly when a person is 35 — matters the most. "Success is multifactorial," he points out. "How did [patients] respond to the meds? That matters, as well as the expertise of the doctor in the lab. These factors are all important in success rates." So while IVF's success varies widely, one estimate from the American Pregnancy Association puts it at 41 to 43 percent for people under 35, and 33 to 36 percent for people from ages 35 to 37. Hodes-Wertz mentioned that the clinic also matters when it comes to success. She says, "Sart.org is helpful at looking at a specific clinic’s rates and the national average for different age groups."

Are there any safety risks?

As with any medical procedure, there are a few safety risks. Batzofin says ovarian hyperstimulation is a potential risk with IVF: "Some women can be very sensitive to the [fertility] medications, so their ovaries can swell up," he explains, "but with competent hands and careful monitoring, the risks can be minimized." As far as the egg retrieval, he says it carries risks of infection, bleeding, and injury to the surrounding structures, although these are rare.

"There is also a risk of ovarian torsion, because the ovaries are enlarged, where the ovaries can twist and could cut off its blood supply, but this occurs rarely," Hodes-Wertz adds. Some research also suggests IVF may slightly increase the chance a baby will be born prematurely or underweight.

OK, so how much does it cost?

IVF treatment is not one-size-fits-all: Depending on what you need and where you're getting treated, there is a wide range in cost. Batzofin says one of the biggest factors in price is geography, as medical costs (like many other costs) vary widely from, for example, New York City to Montana. City-based practices with higher business costs will likely charge more. Batzofin estimates a single cycle can cost from $6,000 to $15,000. Hodes-Wertz's estimate is slightly higher — closer to $12,000 plus an additional $3,000 to $5,000 for medication — though she also acknowledges that there are many factors that go into cost.

IVF does cost a pretty penny, then, but is "an effective treatment, relatively safe in competent hands," Batzofin says. And while it's not a silver-bullet guarantee that you'll get pregnant or have a biological child, it's proven a sound option for many a parent — including some famous ones.

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