Chemical pregnancies are miscarriages that happen at the onset of pregnancy and go unnoticed most of the time. Though definite causes are unknown, fetal abnormalities is one. The mother’s inefficient thyroid gland, uterine abnormalities and/or low ovarian reserve are others. Treatment depends on the cause. Lifestyle management is the only way to prevent recurrence.
So, you’ve been trying to conceive for a while. And just when you thought you were pregnant, bam, you got your periods! One moment you’re pregnant and the next, you’re not. Confused? Trust us, it wasn’t misjudgment. It was what doctors call biochemical pregnancy or just chemical pregnancy.
Chemical pregnancy is actually pregnancy at a very early stage (4-5 weeks from your last period) detectable by its chemical makeup but gets terminated on its own. It happens quickly without warning, with no definite symptoms to nail it. Have your delayed periods come with unusually heavy bleeding with clots and also cramps? Chances are that you have had a chemical pregnancy. It is so common, it actually accounts for 50-75 percent of all miscarriages in the US.1
All chemical pregnancies are miscarriages but all miscarriages are not chemical pregnancies. Unlike miscarriages, chemical pregnancies are not a cause for worry (unless it’s recurring) and your uterine function and periods are back to normal soon.
Understanding Chemical Pregnancy
If you’re still confused what exactly is chemical pregnancy, this is how experts explain it. A fertilized egg gets implanted in your uterus about three weeks after your periods. The cells that prepare to form placenta will start producing the pregnancy hormone hCG or Human Chorionic Gonadotropin rapidly. If you feel something is amiss at this time and go for a pregnancy test, positive result will show on your blood or urine test. In case of a chemical pregnancy, the egg doesn’t get implanted in the uterus and gets eliminated as periods. Since the entire process takes time, your next period will appear a week later with heavy bleeding, with or without cramps, confirming it was, in fact chemical pregnancy.
What Causes It?
There is no definite cause for chemical pregnancies. However, here are some possibilities:
Fetal Or Chromosomal Abnormalities
Chromosomal abnormalities contribute to many spontaneous miscarriages including chemical pregnancies. These abnormalities happen when the genes needed for a baby’s growth are processed at the wrong time, leading to defective chromosomes in the developing fetus that prevents it from sustaining beyond a few weeks.2 3
The mother’s health play a major role in all pregnancies and in bringing the pregnancy to term. Studies have shown that women with subclinical hypothyroidism (SCH, which is a mild thyroid failure) and thyroid autoimmunity (TAI) are more susceptible to complicated pregnancies. A combination of SCH and TAI in women have shown increased chances of miscarriages at a very early stage, which include chemical pregnancies.4
The inability of the fetus to implant normally in the uterine lining is considered another reason for chemical pregnancy. The causes for this could be:
- progesterone hormone not increasing enough to provide adequate uterine lining
- uterine lining or endometrium not thickening despite adequate hormone
- uterine lining having abnormalities like fibroid tumors, scar tissue, etc5
Diminished Ovarian Reserve
Women with low ovarian reserve or insufficient number of eggs to ensure pregnancy have high rates of miscarriages at various stage of pregnancy. Chemical pregnancy, too, cannot be ruled out. 6
Chemical Pregnancy In Assisted Reproduction
It seems that couples who have tried assisted reproduction technologies or ART like IVF have undergone more chemical pregnancies than others. In cases of assisted reproduction, it has been found that apart from the common cause of chromosomal abnormalities or inadequate uterine lining, there are other factors like sperm DNA damage as well as the stress the woman undergoes during the process play a role in biochemical pregnancies.7
There have also been instances of the presence of anti-sperm antibodies in the woman’s body playing spoilsport in her attempt to conceive.8
Can It Be Treated?
It’s true that it’s easier to treat a condition if the cause is known. Since chemical pregnancy comes with no definite cause, any form of treatment could be a long shot. But the good news is, a good number of chemical pregnancies go unnoticed and the women go on to have healthy pregnancies after that. In cases of chemical pregnancies during ART, at least some experts feel that a chemical pregnancy at the beginning of the treatment could be a positive sign that the sperms and egg are doing their job. But it’s definitely a cause for concern if it is recurring, in both spontaneous and assisted pregnancies. In such cases, depending on the cause, treatments like fibroid surgery (if fibroids are present), baby aspirin (to increase the blood flow to the uterus) or hormone treatments (if it’s due to hormone imbalance) are suggested.9
For some couples, psychological counselling is suggested to get over the emotional impact of multiple chemical pregnancies.10
Nothing can go wrong easily in pregnancies if the couples are healthy. Minor lifestyle changes can take care of chemical pregnancies. So, eat healthy, sleep well, manage weight by exercising regularly and have a diet rich in folic acid or supplement the diet adequately.
So, good luck with your next attempt!
References [ + ]
|1, 3, 5.||↑||Pregnancy Complications|
|2.||↑||Rubio, C., C. Simon, F. Vidal, L. Rodrigo, T. Pehlivan, J. Remohi, and A. Pellicer. “Chromosomal abnormalities and embryo development in recurrent miscarriage couples.” Human Reproduction 18, no. 1 (2003): 182-188|
|4.||↑||Liu, Haixia, Zhongyan Shan, Chenyan Li, Jinyuan Mao, Xiaochen Xie, Weiwei Wang, Chenling Fan et al. “Maternal subclinical hypothyroidism, thyroid autoimmunity, and the risk of miscarriage: a prospective cohort study.” Thyroid 24, no. 11 (2014): 1642-1649.|
|6.||↑||Diminished Ovarian Reserve|
|7, 10.||↑||Annan, John Jude Kweku, Anil Gudi, Priya Bhide, Amit Shah, and Roy Homburg. “Biochemical pregnancy during assisted conception: a little bit pregnant.” Journal of clinical medicine research 5, no. 4 (2013): 269.|
|8.||↑||Shibahara, Hiroaki, Mizumi Mitsuo, Yoshikazu Ikeda, Minoru Shigeta, and Koji Koyama. “Effects of Sperm Immobilizing Antibodies on Pregnancy Outcome in Infertile Women Treated With IVF‐ET.” American Journal of Reproductive Immunology 36, no. 2 (1996): 96-100.|