INTRODUCTION:

“Intra-uterine drug delivery is one of the site-specific delivery for the delivery of drugs at uterine especially used for contraception.”

Rationale of IUDDS:

· IUDs are one form of long-acting reversible birth control.

· IUDs are prominently used for contraception and which may be beneficial for family planning.

· Once an IUD is removed, even after long-term use, fertility returns to normal rapidly.

· Copper devices have a failure rate of about 0.8% while hormonal devices fail about 0.2% of the time within the first year of use.

· It can also be used as emergency contraception within 5 days of unprotected sex.

· IUDs do not affect breastfeeding and can be inserted immediately after delivery. They may also be used immediately after an abortion.

· The use of IUDs has increased within the United States from 0.8% in 1995 to 7.2% from the period of 2006 to 2014.The use of IUDs as a form of birth control dates from the 1800s.

Development of IUDs:

· Initially it is constructed from silkworm gut and flexible metal wire e.g. Grafenberg star and ota ring. But it is difficult to insert and insertion and removal process was painful.

· Then several plastic based IUDs of varying sizes and shapes were prepared using inert biocompatible polymers like polyethylene, polypropylene, silicon elastomer.

· Later in modern era well effecient and it is in direct contact with endometrium and several T-shaped Polyethylene devices are developed alongwith non-medicated (Harmonal) IUDs are also emerged.


Fig. 1: Ota Ring	Fig. 2: Grafenberg tube

Fig. 3: T Shaped polyethylene device	Fig. 4: Polymer based IUD

Types of IUDDS:

1. Harmonal:

Progesterone containing IUD

2. Non-harmonal:

Copper containing IUD

1. Harmonal:

Hormonal IUDs (referred to as intrauterine systems in the UK) work by releasing a small amount of levonorgestrel, a progestin. Each type varies in size, amount of levonorgestrel released, and duration. The primary mechanism of action is making the inside of the uterus uninhabitable for sperm. They can also thin the endometrial lining and potentially impair implantation but this is not their usual function. Because they thin the endometrial lining, they can also reduce or even prevent menstrual bleeding. As a result, they are used to treat menorrhagia (heavy menses), once pathologic causes of menorrhagia (such as uterine polyps) have been ruled out.

The progestin released by hormonal IUDs primarily acts locally; use of Mirena results in much lower systemic progestin levels than other very-low-dose progestogen only contraceptives. Hormone-releasing IUDs (made of plastic; steadily release small amounts of hormone progesterone or another progestin such as levenorgesterel). LNG-20 and Progestasert are this type.

Fig. 5: Hormonal IUD-Mirena

2. Non-harmonal:

Most copper IUDs have a T-shaped frame that is wound around with pure electrolytic copper wire and/or has copper collars (sleeves). The arms of the frame hold the IUD in place near the top of the uterus. The Paragard TCu 380a measures 32mm (1.26") horizontally (top of the T), and 36mm (1.42") vertically (leg of the T). Copper IUDs have a first year failure rate ranging from 0.1 to 2.2%. They work by damaging sperm and disrupting their motility so that they are not able to join an egg. Specifically, copper acts as a spermicide within the uterus by increasing levels of copper ions, prostaglandins, and white blood cells within the uterine and tubal fluids. The increased copper ions in the cervical mucus inhibit the sperm's motility and viability, preventing sperm from traveling through the cervical mucus, or destroying it as it passes through.Copper can also alter the endometrial lining, but studies show that while this alteration can prevent implantation of a fertilized egg ("blastocyst"), it cannot disrupt one that has already been implanted.

Advantages of the copper IUD include its ability to provide emergency contraception up to five days after unprotected sex. It is the most effective form of emergency contraception available. It works by preventing fertilization or implantation but does not affect already implanted embryos. It contains no hormones, so it can be used while breastfeeding, and fertility returns quickly after removal.Copper IUDs also last longer and are available in a wider range of sizes and shapes compared to hormonal IUDs.Disadvantages include the possibility of heavier menstrual periods and more painful cramps.

IUDs that contain gold or silver also exist.Other shapes of IUD include the so-called U-shaped IUDs, such as the Load and Multiload, and the frameless IUD that holds several hollow cylindrical minuscule copper beads. It is held in place by a suture (knot) to the fundus of the uterus. It is mainly available in China and Europe. A framed copper IUD called the IUB SCu300 coils when deployed and forms a three-dimensional spherical shape. It is based on a nickel titanium shape memory alloy core. In addition to copper, noble metal and progestogen IUDs; people in China can get copper IUDs with indomethacin. This non-hormonal compound reduces the severity of menstrual bleeding, and these coils are popular.

Fig. 6: Copper-T

Procedure for IUD Insertion:

During the insertion procedure, health care providers use a speculum to find the cervix (the opening to the uterus) and then use an insertion device to place the IUD in the uterus. The insertion device goes through the cervix. The procedure itself, if uncomplicated, should take no more than five to ten minutes.

For immediate postpartum insertion, the IUD is inserted following the removal of the placenta from the uterus. The uterus is larger than baseline following birth, which has important implications for insertion. After vaginal deliveries, insertions can be done using placental forceps, a longer inserter specialized for postpartum insertions, or manually, where the provider uses their hand to insert the IUD in the uterus. After cesarean deliveries, the IUD is placed in the uterus with forceps or manually during surgery prior to suturing the uterine incision.

Generally, the removal is uncomplicated and reported to be not as painful as the insertion because there is no instrument that needs to go through the cervix. This process requires the health care provider to find the cervix with a speculum and then use ring forceps, which only go into the vagina, to grasp the IUD strings and then pull the IUD out.

IUD placement and removal can be taught both by manufacturers and other training facilities.

Mechanism of Intra-uterine devices:

IUDs primarily work by preventing fertilization. The progestogen released from hormonal IUDs mainly works by thickening the cervical mucus, preventing sperm from reaching the fallopian tubes. IUDs may also function by preventing ovulation from occurring but this only occurs partially.

Copper IUDs do not contain any hormones, but release copper ions, which are toxic to sperm. They also cause the uterus and fallopian tubes to produce a fluid that contains white blood cells, copper ions, enzymes, and prostaglandins, which is also toxic to sperm. The very high effectiveness of copper-containing IUDs as emergency contraceptives implies they may also act by preventing implantation of the blastocyst.There are 2 types of IUDs are available: copper and hormonal. Approximately 2% of women who use birth control in the United States currently use IUDs. The most recently introduced hormonal IUD is the levonorgestrel intrauterine system (LNG IUS or Mirena). Worldwide, IUDs are the most inexpensive long-term birth control method available. Hormonal and copper IUDs work in different ways. With a copper IUD, a small amount of copper is released into the uterus. This type of IUD does not affect ovulation or the menstrual cycle. Copper IUDs prevent sperm from being able to go into the egg by immobilizing the sperm on the way to the fallopian tubes. If an egg does become fertilized, implantation on the wall of the uterus is prevented because copper changes the lining of the uterus. With hormonal IUDs, a small amount of progestin or a similar hormone is released into the uterus. These hormones thicken cervical mucus and make it difficult for sperm to enter the cervix. Hormonal IUDs also slow down the growth of the uterine lining, making it inhospitable for fertilized eggs.

Removal Procedure of IUD:

Women should never try to remove an IUD themselves. Serious damage can result. A clinician can usually remove an IUD very simply by carefully pulling the string ends at a certain angle. This causes the IUD arms to fold up and the IUD to slide out through the cervix. If the IUD is being replaced, a new one can usually be inserted immediately. Rarely, the cervix may need to be dilated and a grasping instrument is used to free the IUD. If this occurs, a local anesthetic is used. Very rarely, surgery may be necessary. Women may require hospitalization if an incision is required to remove an IUD.

Advantages of IUDDS:

· Highly effective in preventing pregnancy.

· Inexpensive

· Does not interrupt sex.

· Does not require partner’s involvement.

· Can be used for a long period of time.

· Can be used as an emergency method of birth control.

· An IUD provides long-term contraception for 3 to 5 years and is cost-effective.

· When you are ready to become pregnant, the IUD can be removed by a health-care provider.

· It is convenient. You do not need to remember daily pills.

Disadvantages of IUDDS:

· Does not protect against sexually transmitted infections (STIs).

· If you get a sexually transmitted infection, the IUD could increase the likelihood of developing pelvic inflammatory disease (infection of the reproductive organs).

· May increase the likelihood of ectopic pregnancy (pregnancy outside the uterus).

· Can cause heavier and more painful periods.

· Cramping and discomfort during and 24-48 hours after insertion.

· There are risks during insertion and removal that your clinician should discuss with you before inserting an IUD.

Delusions about IUDDS:

· IUDs can cause infertility

· IUDs should only be used by older and/or monogamous women

· A woman is supposed to have her period regularly to be healthy.

REFERENCES:

1. Winner, B; Peipert, JF; Zhao, Q; Buckel, C; Madden, T; Allsworth, JE; Secura, GM. "Effectiveness of Long-Acting Reversible Contraception". New England Journal of Medicine, 1998-2007; (21)366.

2. Feminist Women’s Health Center at www.FWHC.organd www.Birth-ControlComparison.info

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5. https://en.wikipedia.org/wiki/Intrauterine_device.

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9. Steenland, MW; Tepper, NK; Curtis, KM; Kapp, N. "Intrauterine contraceptive insertion postabortion: a systematic review". Contraception, Nov.2011; 84 (5): 447-64.

10. "Mirena: Levonorgestrel-releasing intrauterine system.

11. By Rose S, Chaudhari A, Peterson. Mirena (Levonorgestrel intrauterine system): a successful novel drug delivery option in contraception. CM. Adv Drug Deliv Rev, Aug.2009; 61(10):808-12.

Received on 11.09.2020 Modified on 09.10.2020

Res. J. Pharma. Dosage Forms and Tech.2021;13(1):72-75.

DOI: 10.5958/0975-4377.2021.00013.6