Hormonska kontracepcija i rizik nastanka venskih tromboembolija

master's thesis

• Title (english): Hormonal contraception and risk of developing venous thromboembolism
• Author: Ivan Vidić
• Mentor: Dinka Pavičić-Baldani (mentor)
• Committee member: Marina Šprem Goldštajn (predsjednik povjerenstva)
• Committee member: Lana Škrgatić (član povjerenstva)
• Committee member: Dinka Pavičić-Baldani (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; (Department of Gynecology and Obstetrics); Zagreb
• Defense date and country: 2014-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Gynecology and Obstetrics

Abstract

Zbog niza kontracepcijskih i nekontracepcijskih dobrobiti te presudne uloge u planiranju obitelji hormonska kontracepcija (HK) nosi titulu „čuvara“ reproduktivnog zdravlja žene. Posebna se važnost primjene HK očituje u sve većem broju neželjenih i neplaniranih trudnoća u mladih žena i adolescentica koje u velikom postotku završavaju namjernim pobačajem, uzrokujući vrlo visoki maternalni mortalitet u zemljama u razvoju. Glavni mehanizam djelovanja je centralni, inhibitorni i sinergistički učinak na sprječavanje ovulacije na razini hipotalamusa i hipofize. Periferni se učinak očituje usporenom proliferacijom i smanjenom receptivnosti endometrija, promjenama cervikalnih faktora i motiliteta jajovoda. Estrogeni izazivaju prokoagulacijski učinak povišenjem plazmatskih koncentracija faktora II, VII, VIII, X i fibrinogena te sniženjem antitrombina III i proteina S kao i nastankom rezistencije na aktivaciju proteina C. Neki gestageni povećavaju razine faktora VII, VIII i X te snižavaju razine proteina S i antitrombina III. Apsolutni rizik nastanka venske tromboembolije (VTE) izražen na 10.000 žena-godina iznosi: 4-5 za nekorisnice te korisnice mini pilula i intrauterinog gestagenskog uloška; 10 za korisnice kombinirane oralne hormonske kontracepcije (OHK) s gestagenima druge generacije; 20 za korisnice OHK s gestagenima treće generacije, vaginalnih prstenova i transdermalnih naljepaka. Uzimajući u obzir da je apsolutni rizik nastanka VTE u trudnoći 29/10.000 te u postpartalnom razdoblju 300-400/10.000 žena godišnje, dolazi se do jasnog zaključka kako je rizik nastanka VTE većine hormonskih kontraceptiva dva do četiri puta veći nego kod nekorisnica, ali zato znatno manji nego za vrijeme trudnoće, a posebice postpartalnog razdoblja. Poštujući svjetske smjernice o primjeni HK u posebno rizičnim skupinama izdvaja se manji broj žena u kojih je primjena HK kontraindicirana. Za sve ostale žene potencijalne kontracepcijske i nekontracepcijske dobrobiti HK uz moguće smanjenje broja neželjenih trudnoća i namjernih pobačaja znatno nadmašuje potencijalne rizike i nuspojave.

Abstract (english)

Due to a variety of contraceptive and non-contraceptive benefits and the critical role in family planning, hormonal contraception is known as "guardian" of female reproductive health. Special importance of hormonal contraception is reflected in the growing number of unwanted and unplanned pregnancies in young women and adolescent girls who end up making a large percentage of intentional abortions; causing very high maternal mortality in developing countries. The main mechanism of action is the central, inhibitory and synergistic effect in preventing ovulation at the level of the hypothalamus and pituitary gland. Peripheral effect manifests slow proliferation and reduced endometrial receptivity, changes in cervical factors and motility of the fallopian tubes. Oestrogens increase plasma concentrations of factors II, VII, VIII, X and fibrinogen, decrease concentration of protein S and antithrombin III and influence resistance in the activation of protein C. Some gestagens increase the level of factors VII, VIII and X and decrease levels of protein S and antithrombin III. The absolute risk of venous thromboembolism (VTE) expressed per 10.000 women-years is: 4-5 for nonusers, women using progestin-only pills or progestin intrauterine devices; 10 for users of oral contraceptive pills (OCPs) with second-generation gestagens; 20 for users of OCPs with third-generation gestagens, vaginal rings and transdermal patch. Taking into account that the absolute risk of VTE in pregnancy is 29/10.000, or in the postpartum period 300-400/10.000 women a year; clear conclusion is that the risk of VTE for most hormonal contraceptives is two to four times higher than among non-users, but at the same time significantly lower than during pregnancy, especially postpartum period. Following the international guidelines on use of hormonal contraceptives in high-risk groups, a small percentage of woman in which the use of these drugs is contraindicated stands out. For all other women contraceptive and noncontraceptive benefits of hormonal contraception, as well as dramatically reduce of unwanted pregnancies and intentional abortions far exceed the potential risks and side effects.

• Keywords: oralni hormonski kontraceptivi; rizični čimbenici; venska tromboembolija
• Keywords (english): hormonal oral contraceptives; risk factors; venous thromboembolism
• Language: croatian
• URN:NBN: urn:nbn:hr:105:319981
• Study programme: Title: Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica medicine (doktor/doktorica medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2015-09-16 12:24:17