During research for my book Facing Miscarriage, I stumbled across an article in the British news source, The Telegraph, talking about a “panic” that spread across the UK when early detection home pregnant tests first became available a few years ago.

I didn’t find any similar articles in US papers, but it’s easy to see why the new home pregnancy tests could cause a flurry of concern.

Old-style tests, manufactured prior to 2004, typically looked for a pregnancy hormone level of 50-100 mIU/ml and were not effective until the day a woman missed her period, on average, about 14 days post fertilization. This is when the baby is well implanted and the miscarriage rate is expected to be between 8 and 20 percent.

The new tests, however, detect the hormone at 20 mIU/ml. This is within a day or two of implantation, more like 9-10 days after fertilization.

Since the advent of early sonography, we’ve known that a huge number of fertilized eggs either never implant at all, or attempt implantation and fail. This number varies depending on who you ask, but is always frighteningly high — between 50 and 75 percent.

For many moms, working so hard to achieve pregnancy and the family of their dreams, this is a terrible and sad loss. The emotional pain in getting their period after seeing a positive pregnancy test is often strong and frightening.

These early losses, however, almost never indicate a problem that needs treatment. The fusing of the egg and sperm’s genetic material is tricky and often goes awry, either misaligning or dividing improperly in early cell growth. When the egg with chromosomal errors bumps against the uterus, the body will start the implantation process. This sets off the manufacture of pregnancy hormone, but often, the lining rejects the egg. In this case, the woman’s body will register a fleeting rise in pregnancy hormone even though the baby could not implant and grow. The new tests are so sensitive as to catch the temporary rise.

This early chromosomal rejection has no bearing on the health of the mother or her ability to carry children to term. The rush of hospital visits by distressed moms causes extra upset and frustration. They often find they are simply turned away. Others might be subjected to invasive and unnecessary tests. The problem amplifies — moms want their babies to be recognized from conception, and health care providers want to maintain a simplicity in diagnosis and treatment of clinically recognized pregnancy and miscarriage.

As I write what I hope to be the newest book about miscarriage and how to get through it, I will address the issue of the new definition of miscarriage. Do we adjust our statistics and scare women with the real figure — that over half of their pregnancies will be lost before week 5? And how do we decide when a woman actually needs intervention for recurring miscarriages? Do early losses simply “not count” anymore? I do wish sites like this one that advocate super-early testing also include a reminder of how common an early loss can be.

Perhaps we will rewrite the rules based on our early detection of pregnancies, creating a hierarchy of risk based on gestational age. But the rules will be for treatment and clinical relevance only. Our babies are our babies, whether at 16 cells or fully formed in our waiting arms.