Amy Klein with her daughter. (CHARLOTTE CRAWFORD)

When I first visited a fertility doctor because of pregnancy problems, I had no idea that the in vitro fertilization, or IVF, he was suggesting to help me was actually the “test-tube baby” technique that I’d heard about, an approach that had sounded scary, like something out of science fiction.

After I educated myself and started treatment, the concerns continued: Would the hormone-stimulating drugs have adverse effects on me? What would the drugs do to the fetus? And more important, would conceiving a child outside the womb (not actually in a test tube but in an embryology lab) have any long-term effects? Most important, would my child — if I would be lucky enough to give birth to one — be as physically and mentally healthy as naturally conceived children?

Articles and blogs fed into my worries — not to mention the online “mommy boards” at pregnancy and fertility websites where women trade rumors, innuendoes and fears, often based on nothing more than a friend’s experience.

Since the first test-tube baby, Louise Brown, was born in England in 1978, about 6.5 million children have been born worldwide with the help of assisted reproductive technologies (ART) such as IVF. So there is now enough information to address my concerns. Overall, those findings leave me pretty confident that the risks are pretty small and well worth taking if, like me, you want to have a baby but can’t.

Although taking fertility medications drove me crazy — some hormones gave me nightmares, others kept me up at night, and the main ones made my mind race loopily — looking at studies allowed me to conclude that IVF probably has no long-term bad effects.

For instance, a 2013 study of 21,646 women in Australia concluded that “there is no evidence of an increased risk of ovarian cancer following IVF in women who give birth.” Another study of 9,825 American women found no link between gonadotropins — the drugs I was taking to increase my egg production — and ovarian cancer for women who gave birth. There was one worrisome point: Both studies found an increased cancer risk for women with “resistant infertility” — i.e., those who did not give birth — although the researchers did not know why.

A recent study in the journal JAMA of about 25,000 women who had fertility treatments between 1980 and 1995 found that those who had gone through IVF had no greater risk of getting breast cancer in the subsequent 21 years than those who used other techniques.

Whew. I went through nine rounds of IVF before I got pregnant, which means I took a lot of ovary-stimulating drugs, so these studies are reassuring.

“Numerous studies and opinions from [the American Society for Reproductive Medicine] confirm low risk for ovarian and breast cancer from the use of fertility drugs, regardless of the number of IVF cycles performed,” said Jeffrey Braverman, founder and medical director at Braverman IVF & Reproductive Immunology in New York.

So how about risks to the baby? Would he or she be affected by her medically assisted conception?

Two studies have raised concerns.

A 2016 study in JAMA Pediatrics found increased risk for birth defects in babies conceived through ART. The study, which involved more than 4 million infants, found that “singleton infants conceived using ART were 40 percent more likely to have a nonchromosomal birth defect (such as cleft lip and/or palate or a congenital heart defect) compared with all other singleton births.”

The researchers acknowledged that the study “did not account for some factors related to infertility that might explain the observed increases in risk for birth defects.” In other words, IVF may not have caused the defects. They recommended further research.

A comprehensive review of a group of other studies suggested that the risk for developmental disabilities was greater with ART — which, in addition to IVF, includes egg freezing and surrogacy — than with natural childbirth. The review examined studies of IVF and autism, cerebral palsy, intellectual disability, attention-deficit/hyperactivity disorder and sensory impairment, among others, and found conflicting information, no correlation or that the disabilities could have been caused by other factors such as preterm birth.

And a study published in March found an increased risk of neoplasms — tumors that can be benign or malignant — in children born through ART.

But I focused on a study that followed children conceived with ART into their teenage years. It offers a much more reassuring view. The study, published in January, compared 253 16- and 17-year-olds who were conceived with fertility treatments to a cohort of teenagers conceived naturally and found that “no differences were detected in general and mental health of ART adolescents or cognitive ability, compared with the reference group.” The researchers, who said this was the first long-term study of such children, concluded that their “preliminary results provide reassurance that in the long run, health and functioning of ART-conceived adolescents is not compromised.”

One of the researchers on the study, Mark Weiser, a psychiatry professor at Tel Aviv University’s Sackler School of Medicine, said in an interview that the findings should be a relief to parents who used IVF and other assisted reproductive technology. “We show there is nothing wrong with these kids” when compared with children born naturally. “This is a very positive message to parents who are not able to get pregnant on their own. If you look down the line, the kids are perfectly normal.”

As for me: After an uneventful pregnancy, my daughter was born full term nearly two years ago at a healthy six pounds, six ounces, with all her fingers and toes and brown hair that would soon turn to curls. She is a delightful, chatty, feisty toddler. Every parent worries about their child, and I know that I will be no different. But for now it seems clear to me that the risks of having used IVF were minimal — and the reward huge.