Ectopic pregnancy risk factors
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Moises Romo M.D.
Overview
Ectopic pregnancy usually occurs in women with fallopian tube dysfunction. There are a number of risk factors for ectopic pregnancies, among them pelvic inflammatory disease, infertility, DES exposure, tubal surgery, smoking, previous ectopic pregnancy, multiple sexual partners, current IUD use, tubal ligation, and previous abortion. The most potent risk factor in the development of ectopic pregnancy is tubal surgery.
Risk Factors
- Risk factors in the development of ectopic pregnancies may be occupational, environmental, genetic, and viral. The following table summarizes these risks and its odds ratio:
| Risk Factors Odds Ratios for Ectopic Pregnancy | |
| Risk Factor | Odds Ratio |
| Tubal surgery | 21 |
| Tubal ligation | 9.3 |
| Previous ectopic pregnancy | 8.3 |
| In-utero DES exposure | 5.6 |
| IUD | 4.2 – 45 |
| Documented tubal pathology | 3.8 – 21 |
| Infertility | 2.5 – 21 |
| Previous STD | 2.5 – 3.7 |
| Multiple sexual partners | 2.1 |
| Prior pelvic / abd surgery | 0.9 – 3.8 |
| Cigarette smoking | 2.3 – 2.5 |
| Vaginal douching | 1.1 – 3.1 |
| 1st intercourse < 18 years old | 1.6 |
Common Risk Factors
- Tubal surgery. It is known as the major risk factor for ectopic pregnancy developemnt.[1][2]
- Tubal ligation. Although tubal ligation is highly effective in preventing pregnancies, if a pregnancy does occur, it is more likely to be ectopic.[3]
- Previous ectopic pregnancy. Same as having a previous ectopic pregnancy increases the risk for further ectopic pregnancies, having a intrauterine pregnancy decreases this risk.[4][./Ectopic_pregnancy_risk_factors#cite_note-pmid8641479-1 [4]][5][6]
- In-utero DES exposure. The usage causes a loss of fimbriae and stenosis of fallopian tubes, which may increase up to 3 times the risk of ectopic pregnancy as compared to unexposed women.[7]
- IUD. It is thought that IUD-induced inflammation may result in deciliation of the endosalpinx and then delays ovum transport, altough, the exact mechanism is not fully understood.[4]
- Documented tubal pathology. Ectopic tubal pregnancy may occur in a blocked tube with contralateral tubal patency, although, this association was found to be weaker for those with two blocked tubes.[8][9]
Less common Risk Factors
- Infertility. Treatment of infertility, such as in vitro fertilization is associated with a 2 – 3 % increased risk compared with the general population.[10][11][12]
- Previous STD. This possibly due to tubal scarring from gonococcal and chlamydial infections, which produce changes in tubal function leading to delay in ovum transport and tubal implantation.[4][7]
- Multiple sexual partners. There has been an association between multiple sexual partners and ectopic pregnancies, especially when 1st intercourse < 18 years old.[7]
- Prior pelvic / abdominal surgery. Women with histories of laparotomy and appendectomy have higher risk of developing an ectopic pregnancy, although this risks increases even higher when it involves tubal involvement.[13]
- Cigarette smoking. Inhalation of cigarette smoke may impair fallopian tube function by affecting on ciliary beat frequency and smooth muscle contraction.[14][15]
- Pior abortions. There is conflict between studies in revealing an association; the cause of this relationship is most likely due to infection, hormonal imbalance, or immunologic factors.[16][17]
- Advanced age. There is a 9 times-fold increased risk of developing an ectopic pregnancy in women ≥39 as compared with those ≤26 years.[18][4]
- Vaginal douching. It is thought by some to increase ectopic pregnancies.
References
- ↑ Ankum WM, Mol BW, Van der Veen F, Bossuyt PM (June 1996). “Risk factors for ectopic pregnancy: a meta-analysis”. Fertil Steril. 65 (6): 1093–9. PMID 8641479.
- ↑ Ankum WM, Mol BW, Van der Veen F, Bossuyt PM (June 1996). “Risk factors for ectopic pregnancy: a meta-analysis”. Fertil Steril. 65 (6): 1093–9. PMID 8641479.
- ↑ Furlong LA (November 2002). “Ectopic pregnancy risk when contraception fails. A review”. J Reprod Med. 47 (11): 881–5. PMID 12497674.
- ↑ 4.0 4.1 4.2 4.3 Ankum WM, Mol BW, Van der Veen F, Bossuyt PM (June 1996). “Risk factors for ectopic pregnancy: a meta-analysis”. Fertil Steril. 65 (6): 1093–9. PMID 8641479.
- ↑ Barnhart KT, Sammel MD, Gracia CR, Chittams J, Hummel AC, Shaunik A (July 2006). “Risk factors for ectopic pregnancy in women with symptomatic first-trimester pregnancies”. Fertil Steril. 86 (1): 36–43. doi:10.1016/j.fertnstert.2005.12.023. PMID 16730724.
- ↑ Coste J, Bouyer J, Job-Spira N (February 1997). “Construction of composite scales for risk assessment in epidemiology: an application to ectopic pregnancy”. Am J Epidemiol. 145 (3): 278–89. doi:10.1093/oxfordjournals.aje.a009101. PMID 9012601.
- ↑ 7.0 7.1 7.2 Burton JL, Lidbury EA, Gillespie AM, Tidy JA, Smith O, Lawry J, Hancock BW, Wells M (May 2001). “Over-diagnosis of hydatidiform mole in early tubal ectopic pregnancy”. Histopathology. 38 (5): 409–17. doi:10.1046/j.1365-2559.2001.01151.x. PMID 11422477.
- ↑ “www.moscmm.org” (PDF).
- ↑ Russell JB (March 1987). “The etiology of ectopic pregnancy”. Clin Obstet Gynecol. 30 (1): 181–90. doi:10.1097/00003081-198703000-00025. PMID 2953513.
- ↑ Maccato M, Estrada R, Hammill H, Faro S (February 1992). “Prevalence of active Chlamydia trachomatis infection at the time of exploratory laparotomy for ectopic pregnancy”. Obstet Gynecol. 79 (2): 211–3. PMID 1731286.
- ↑ Coste J, Bouyer J, Job-Spira N (February 1997). “Construction of composite scales for risk assessment in epidemiology: an application to ectopic pregnancy”. Am J Epidemiol. 145 (3): 278–89. doi:10.1093/oxfordjournals.aje.a009101. PMID 9012601.
- ↑ Ankum WM, Mol BW, Van der Veen F, Bossuyt PM (June 1996). “Risk factors for ectopic pregnancy: a meta-analysis”. Fertil Steril. 65 (6): 1093–9. PMID 8641479.
- ↑ Parazzini F, Tozzi L, Ferraroni M, Bocciolone L, La Vecchia C, Fedele L (November 1992). “Risk factors for ectopic pregnancy: an Italian case-control study”. Obstet Gynecol. 80 (5): 821–6. PMID 1407922.
- ↑ Bouyer J, Coste J, Shojaei T, Pouly JL, Fernandez H, Gerbaud L, Job-Spira N (February 2003). “Risk factors for ectopic pregnancy: a comprehensive analysis based on a large case-control, population-based study in France”. Am J Epidemiol. 157 (3): 185–94. doi:10.1093/aje/kwf190. PMID 12543617.
- ↑ Tay JI, Moore J, Walker JJ (April 2000). “Ectopic pregnancy”. BMJ. 320 (7239): 916–9. doi:10.1136/bmj.320.7239.916. PMC 1117838. PMID 10742003.
- ↑ Bouyer J, Rachou E, Germain E, Fernandez H, Coste J, Pouly JL, Job-Spira N (November 2000). “Risk factors for extrauterine pregnancy in women using an intrauterine device”. Fertil Steril. 74 (5): 899–908. doi:10.1016/s0015-0282(00)01605-8. PMID 11056230.
- ↑ Honoré LH (October 1979). “A significant association between spontaneous abortion and tubal ectopic pregnancy”. Fertil Steril. 32 (4): 401–2. doi:10.1016/s0015-0282(16)44294-9. PMID 488425.
- ↑ Mäkinen JI, Erkkola RU, Laippala PJ (March 1989). “Causes of the increase in the incidence of ectopic pregnancy. A study on 1017 patients from 1966 to 1985 in Turku, Finland”. Am J Obstet Gynecol. 160 (3): 642–6. doi:10.1016/s0002-9378(89)80047-x. PMID 2929684.
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